There is increasing interest in the application of solar energy for widespread consumer use. Solar hot water units are becoming accepted, but home heating and cooling systems are still rarely used as of this time. The high initial cost and complexity of active systems may preclude large scale use for many years to come.
Passive systems for heating and cooling of buildings use a minimum of mechanical power to collect or distribute solar energy. One example is the passive roof pond which has been used in flat roof homes in the Southwestern United States. The simplicity of the passive roof pond usually results in a more reliable and less expensive solar system than the active systems with their complex heat exchangers, collectors and pumps.
One problem with passive system of the roof pond type is the fact they are only applicable to flat roofs. It would certainly constitute a forward step in the art if the principles of passive systems could be utilized in homes having pitched roofs. Such a system avoids the expense inherent in active systems and yet would not destroy the architectural features of the home or other building utilizing such a system.